1. Field of the Invention
The present invention relates to an air supply and exhaust structure for a fuel cell for supplying reaction air to the fuel cell and discharging the reaction air passing through the fuel cell.
2. Related Art
A fuel cell, particularly an air-cooling fuel cell, takes in reaction air by operation of a blower and also performs cooling with use of the reaction air. However, at the time of low temperature such as in winter and other occasions, the fuel cell is put in a supercooled state, which may deteriorate starting performance of the fuel cell. As a countermeasure to solve such defective matter, Patent Document 1 (Japanese Patent Laid-Open No. 2007-184110) and Patent Document 2 (Japanese Patent Laid-Open No. 2009-26486) disclose a technology of using air warmed by a fuel cell.
More specifically, in Patent Document 1, a heat exchanger is placed inside an exhaust duct, and exhaust heat is transmitted via a heat carrier to a heat exchanger disposed inside an intake duct so as to warm the reaction air to be introduced to a fuel cell, and according to such manner, the starting performance of the fuel cell at the time of low temperature is enhanced. In Patent Document 2, exhaust air (warm air) discharged from a condenser is introduced to a periphery of the fuel cell through an air conduit, and according to such manner, the starting performance of the fuel cell at the time of low temperature is enhanced.
However, in the technologies in Patent Documents 1 and 2, it is required to arrange a pipe or an air conduit for circulating a heat carrier in a fuel cell system, which leads to the upsizing of the fuel cell system and complicated structure, and which hence results in negative effect for mounting the fuel cell system to a vehicle.